Select the shape of the pulses and then run the time control to watch the pulses pass through one another, temporarily interfering when they are superposed. You can adjust the second pulse height with the slider control or use a normalize button to exactly match or cancel the first pulse.
Superposition is fundamental to wave behavior: the amplitude of the combination is simply the sum of the amplitudes of the various wave components. This can be most clearly seen in the superposition of traveling wave pulses—individual, nonperiodic disturbances. This Demonstration gives a one-dimensional view of how wave pulses pass through one another, interfering to form a larger or smaller pulse, or canceling completely, before continuing on in their original shape. When applied to a periodic wave (which can be thought of as a train of pulses), superposition results in interference phenomena such as standing waves, the nodes being points where permanent cancellation occurs.